Charter ARP Leak

Larry Sheldon larrysheldon at
Tue Dec 30 01:21:28 UTC 2014

On 12/29/2014 11:35, Brett Frankenberger wrote:
> On Mon, Dec 29, 2014 at 12:27:04PM -0500, Jay Ashworth wrote:
>>> Valdis, you are correct. What your seeing is caused by multiple IP
>>> blocks being assigned to the same CMTS interface.
>> Am I incorrect, though, in believing that ARP packets should only be visible
>> within a broadcast domain,
> broadcast domain != subnet

It surprises me that in this day and age, in a forum like this that has 
an active thread about kids being taught archaic concepts, we see 
language like "broadcast domain != subnet" and a perceived need to 
explain it.

[no longer germane material deleted to reduce excess baggage charges]

> int ethernet 0/0
>    ip address
>    ip address secondary
>    ip address secondary
> The broadcast domain will have ARP broadcasts for all three subnets.

This are not "subnets"!  They are IP addresses in three different IP 

> Doing it over a CMTS doesn't change that.

Communication here perceived as hostile is apologized-for.

The unique Characteristics of System Administrators:

The fact that they are infallible; and,

The fact that they learn from their mistakes.

Quis custodiet ipsos custodes

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